Lexuss
latest luxury crossover,
the RX 450, has been wafting into the
UK since January, steadily adding
to the 43,000 RX models already sold
here over the years. Today, the RX
is Lexuss
best-selling model world-
wide and youll
need a minimum of
£39,995 to put one on your drive...

BUT
EVEN THAT
WILL ONLY BUY you a two-wheel drive 200t S 2.0-litre petrol version. If you
want more kerb appeal, more power and more oomph then dig deep 
£57,995 will get you a 3.5-litre V6 petrol hybrid with four-wheel drive.

However much you spend the RX is easily identified by its huge, gaping grille
flanked by sleek headlights. The front, sides and rear of the body all feature
sharply-creased 'origami' styling lines and chamfered body panels. And it really
is worth taking a few minutes just to look at the detail and how the body panels,
both tiny and large, are creased and pressed into aerodynamically-efficient
shapes.

This new Lexus RX has a bold and larger five-door, five-seater body with a coupe-esque
side profile. There has been a 120mm increase lengthwise, to 4,890mm, which
allows for a longer wheelbase; the width has also been increased making it feel
and look much roomier. At the rear sits a 453-litre boot with a bumper-level
rear load floor; fold down the split rear seats and the cargo space goes up
to 924 litres.

These
new RXs are
faster, more efficient,
and more luxurious and
have a re-engineered
hybrid powertrain
plus there are also less
expensive 2.0-litre turbo
petrol versions...

Overall these new RXs are faster, more efficient, and more luxurious 
and very comfortable and quiet. There's also a re-engineered hybrid powertrain
as well as less expensive versions powered by a new 2.0-litre turbo petrol engine.
Safety and driver assistance functions have also been improved.

The only obvious technology missing from the hybrid versions is the must-have
plug-in (PHEV) system made so popular by Mitsubishi and which dramatically improves
fuel economy and lowers emissions as well as reducing road tax and company car
Benefit-in-Kind tax.

Inside the RX 450 you'll find leather trim and upholstery, all beautifully shaped
and very cosseting. The dash is greatly improved and designed to provide a 'cockpit'
effect on the driver's side; a large centre stack houses the radio and heating/ventilation
controls.

A stylish analogue clock tops the centre console which is home to the automatic
transmission's gearshift lever, the driving mode selector (Eco, Normal, Sport
and Sport+), electronic handbrake and a very fiddly and erratic 'mouse'-style
controller for the widescreen information and SatNav display.

Officially
the Combined
Cycle fuel consumption
is 51.4mpg but real-life
fuel economy isnt
that great  on test a
disappointing 31.5mpg
overall...

The
hybrid powertrain uses a re-worked 3.5-litre V6 direct injection, normally-aspirated
petrol engine which combines with front and rear electric motors to give a total
power output of 308bhp and 247lb ft of torque delivered at 4,600rpm.

The
Combined Cycle fuel consumption is officially 51.4mpg and CO2 emissions 127g/km,
giving £0 First Year road tax (£110 thereafter). Company car drivers will pay
22% Benefit-in-Kind tax  substantially more than the 7 to 15% paid by
business users for most other PHEV (petrol-electric plug-in hybrid) SUVs.

The
Lexus hybrid system uses twin electric motors to reduce the load on the large
petrol engine and to boost acceleration. The motors work all the time while
the petrol unit will stop and start at any vehicle speed (depending on a variety
of conditions) to maintain a balance between performance and fuel efficiency.

The battery pack is recharged during de-acceleration or on the over-run going
down hills or when slowing to a lower speed or to a stop. The rear electric
motor also acts as a generator to charge the battery in regenerative braking
mode.

The hybrid will also pull away from standstill in silence and cover a couple
of miles on electric power alone. The four-wheel drive system is an on-demand
function and only comes into use when extra traction is needed. However, the
RX 450h doesn't have a plug-in recharge system and consequently real-life fuel
economy isn't that great, although to some extent it does reduce the amount
of petrol used.

Driven mostly in Eco mode  covering 200 miles of motorways, some A/B roads
and some in-town driving  registered a disappointing 31.5mpg overall.
The best figure according to the onboard computer was just one short journey
when 35.8mpg was recorded. Long journeys do take a serious toll on fuel economy
although the driving refinement is superb.

A
big improvement has
been made to the
electric-controlled CVT
automatic transmission.
It feels less strained and
power-sapping and
theres a healthy shove of
acceleration as it nips to
62mph in 7.7 seconds...

A
big improvement has been made to the 450h's electric-controlled CVT automatic
transmission  during acceleration it feels less strained and power-sapping
than before, and the engine sounds less stressed. There's a healthy shove of
acceleration as attested to by the zero-to-62mph figure of 7.7 seconds. Top
speed is 124mph.

While the electric motors enhance the performance they do less to reduce fuel
consumption during real-life driving conditions  something a PHEV plug-in
hybrid will do over longer driving distances.

As
for driveability and ride comfort, the RX 450h is generally very good for such
a large vehicle. The ride is really comfortable as the suspension is set-up
on the soft side so there is some body-roll during cornering. But only one spec
 the F-Sport  includes adjustable rate air-suspension which sharpens
the handling when needed. Noise intrusion from both wind and road surfaces is
minimal and combined with a low engine tone makes the RX 450h a relaxing drive.
It's just a shame it's not more fuel- and CO2-efficient.

Strong reasons to buy a RX 450h include its great road presence, superb quality
and high spec, luxurious and roomy interior, comfortable ride, and the strong
and smooth power delivery. Alongside that though it's expensive and its poor
real-life fuel economy falls well below the official figure. ~ David
Miles